1. Field of the Invention
The invention relates to a hand-operable press for resizing spent rifle and pistol cartridges, prior to their being primed and recharged with a bullet, and to a method of using the press to resize the cartridges.
2. Discussion of Prior Art
When a cartridge is fired in a rifle or pistol, the firing pin of the gun compresses the primer of the cartridge, which in turn causes the primer to ignite. The primer then ignites the main powder charge of the cartridge, thereby generating pressure which expands the metallic, e.g., brass, cartridge until it reaches the interior diameter of the gun chamber, thus sealing the chamber for a more efficient expulsion of the bullet.
After the bullet exits from the gun barrel, the pressure decreases, allowing the cartridge to contract slightly toward its prefiring size. The cartridge, however, does not completely return to its size, and thus cannot be reused unless it is reshaped.
In order for the spent cartridge to be reused, its walls must be contracted (i.e., resized) to its original prefiring size, any spent primer must be ejected from the cartridge, a new primer must be inserted into the cartridge, new powder must be added, and the bullet must be replaced.
Cartridge resizing and reloading devices have previously been developed. The patent to SCHAENZER, U.S. Pat. No. 4,325,282, discloses a hand-operated device for reloading and resizing cartridges. The resizing is accomplished by placing a resizing die vertically over a spent cartridge and tapping the top surface of the die with a rubber mallet until the die is forced over the cartridge and the cartridge is resized to the dimensions of the bore of the die. Once the cartridge has been shaped, an elongated rod is inserted into the bore of the die through the mouth of the cartridge and is tapped with a rubber mallet until the cartridge is freed from the die.
HAZEL, U.S. Pat. No. 3,771,411, also discloses a manually operable cartridge loading and resizing device. The device prepares a spent shotgun cartridge for reloading by inserting an empty cartridge onto a loading ram, and by then lowering a punch into the cartridge, which punches out the spent primer. Thereafter, the cartridge is resized by forcing a resizing die over the cartridge so that it is compressed within the bore of the die.
DEITEMEYER, U.S. Pat. No. 3,001,436, discloses a soft-shell loader and cartridge resizing press comprising a substantially horizontal base portion having upright standards and a supply support. The support includes a resizing and crimping tool which is reciprocable within a vertical bore. In order to resize a cartridge, a shell is placed above a metallic ring, and the handle is rotated towards the base of the device in order to compress the shell into the desired shape.
LEE, U.S. Pat. No. 4,177,711, discloses a shotgun loading device in the form of a press. The press includes a base having an upstanding column and a reciprocable arm and handle. To reshape a cartridge, a ram element with a central pin is used to force a ring over a shell. The pin pushes the primer from the cartridge.
BACHHUBER, U.S. Pat. No. 3,157,086, discloses a shell reloading device with a vertically reciprocable carriage. A tool having a pair of sizing dies is attached to the carriage, and is operator-activated via a handle and lever.
VEUM, U.S. Pat. No. 2,807,186, discloses a shotgun shell reconditioning press. It is capable of resizing a shell by using a cylindrical die to encase a shell. An operating handle is used to manipulate the resizing case and the knockout assembly.
None of the prior art, however, discloses a cartridge resizing press which can operate at relatively low volumes for resizing cartridges in as simple and efficient a manner as the present invention. Nor is any of the prior art capable of providing a temporary, e.g., tabletop, operation, or a permanently mounted operation as in the present invention.